Sutter's Mill was a water-powered sawmill on the bank of the South Fork American River in the foothills of the Sierra Nevada in California. It was named after its owner John Sutter. A worker constructing the mill, James W. Marshall, found gold there in 1848. This discovery set off the California Gold Rush (1848–1855), a major event in the history of the United States.

New Helvetia, meaning "New Switzerland", was a 19th-century Alta California settlement and rancho, centered in present-day Sacramento, California.